// 输入页码后直接查询当前页
function changePageNum(pageNum,name,category,state) {
     params = ""
     if(name.length!=0 && name!=''){
         params += "&name="+name
     }
    if(category.length!=0 && category!=''){
        params += "&category="+category
    }
    if(state.length!=0 && state!=''){
        params += "&state="+state
    }
    // alert(params)
    window.location.href="ProductListServlet?pageNum="+pageNum+params
}
